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Investment Securities (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2018 | Dec. 31, 2017
Available for sale |  |
Total investment securities available for sale, Amortized Cost | $ 68,939 | $ 68,181
Total investment securities available for sale, Gross Unrealized Gains | 56 | 185
Total investment securities available for sale, Gross Unrealized Losses | 2,109 | 763
Available-for-sale securities, investment securities, Fair Value | 66,886 | 67,603
US government agencies [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 8,981 | 8,749
Total investment securities available for sale, Gross Unrealized Gains | 2 | 1
Total investment securities available for sale, Gross Unrealized Losses | 349 | 97
Available-for-sale securities, investment securities, Fair Value | 8,634 | 8,653
SBA securities [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 3,635 | 4,087
Total investment securities available for sale, Gross Unrealized Gains |  |
Total investment securities available for sale, Gross Unrealized Losses | 163 | 24
Available-for-sale securities, investment securities, Fair Value | 3,472 | 4,063
State and political subdivisions [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 8,460 | 11,242
Total investment securities available for sale, Gross Unrealized Gains | 39 | 179
Total investment securities available for sale, Gross Unrealized Losses | 127 | 25
Available-for-sale securities, investment securities, Fair Value | 8,372 | 11,396
Asset-backed securities [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 6,583 |
Total investment securities available for sale, Gross Unrealized Gains | 13 |
Total investment securities available for sale, Gross Unrealized Losses | 10 |
Available-for-sale securities, investment securities, Fair Value | 6,586 |
Mortgage-backed securities [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 41,280 | 44,103
Total investment securities available for sale, Gross Unrealized Gains | 2 | 5
Total investment securities available for sale, Gross Unrealized Losses | 1,460 | 617
Available-for-sale securities, investment securities, Fair Value | 39,822 | 43,491
Mortgage-backed securities [Member] | FHLMC [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 8,012 | 9,102
Total investment securities available for sale, Gross Unrealized Gains |  |
Total investment securities available for sale, Gross Unrealized Losses | 361 | 149
Available-for-sale securities, investment securities, Fair Value | 7,651 | 8,953
Mortgage-backed securities [Member] | FNMA [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 30,100 | 29,383
Total investment securities available for sale, Gross Unrealized Gains | 1 | 3
Total investment securities available for sale, Gross Unrealized Losses | 933 | 386
Available-for-sale securities, investment securities, Fair Value | 29,168 | 29,000
Mortgage-backed securities [Member] | GNMA [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 3,168 | 5,618
Total investment securities available for sale, Gross Unrealized Gains | 1 | 2
Total investment securities available for sale, Gross Unrealized Losses | 166 | 82
Available-for-sale securities, investment securities, Fair Value | $ 3,003 | $ 5,538

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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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